Rubber compound and the method of making same.



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EEWXN E. A G. MEYER, O]? DETROIT, MICHIGAN, ASSIGNOR T0 MORGAN & WRIGHT,A

CORPORATION OF MICHIGAN.

RUBBER. COMPOUND AND THE METHOD OF MAKING SAME.

misses,

Ho Drawing.

To all whom itmay concern:

Be it known that I, ERWIN E. A. G. MEYER, a subject of the Emperor ofGermany, and a resident of Detroit, county of Wayne, and State ofMichigan, have invented certain .new and useful Improvements in -RubberCompounds and the Methods of Making Same, of which the following is afull, clear, and exact description.

This invention relates to rubber compounds and the method of makingsame, and more particularly to a compound including therein high grade,rubber.

By my invention I am enabled to produce a rubber compound, the base ofwhich is a high grade stifi' rubber, such as Ceylon or Para rubbers,which compound will possess properties imparting thereto aftervulcanization, inherent characteristics and a finish which are commonlyfound only in softer rubbers such as Guayule and some African rubbers,while retaining the superior quality of the base. I have found thatwhile the base of this compound is a high grade, stifi' rubber, theother ingredients pr agents, compounded therewith, will not only modifythe natural properties of this rubber, but will combine therewith, in amanner and in such proportion as to enable me to produce this compoundat a cost to adapt it for usein commercial competition with the cheapernatural products.

- To secure the desired result, I have found it necessary to combine therubber and other ingredients in a particular manner, in order to enablenee to incorporate in the compound a sufficient quantity or volume ofthe modifying or softening agent.

My invention consists in a rubber compound embodying therein anadmixture of a high grade stifirubber and an unctuous softening aent,'in such proportions as to impart to t e compound, aftervulcanization, softness, a high degree of elasticity and smoothness offinish; and in other novel characteristics, and the novel method ofcombining the rubber and the softening agent, all as hereinafter setforth and described and. more particularly pointed out in the claimshereto appended.-

it rubber compound such templated by my invention adapted for use inproduct tubes vesicle tire. for r Specification of Letters Patent.

' Patented Oct. 9, 1917..

Application filed March 7, 19%. Serial No. 823,181.

in which softness of texture, high elasticity and smoothness of finishare essential, or desirable, characteristics.

At the present time articles of this character are sometimes made fromrelatively low grade rubbers, such as Guayule and soft African rubbers,the peculiar proper ties of which are imparted thereto by naturalingredients such as resins. At the present time the available supply ofsuch rubbers is limited, and it is therefore highly desirable to securea satisfactory substitute therefor.

While naturally, high grade stiff rubber, such as Ceylon or Pararubbers, are unsuited for use in the production of articles of thischaracter, because of the absence of natural ingredients impartingthereto the necessary softness, I am enabled, by mixing therewithcertain modifying or softening agents, to produce a compound dissimilarfrom Guayule or soft African rubbers, but possessing those propertieswhich will adapt it to the same uses as theseinatural products. At thesame time, my compound is superior in uniformity and various otherimportant characteristics to the natural rubbers.

' By mixing with a high grade stiff rubher, such as Ceylon or Pararubber, an unctuous substance, such as petrolatum, in such proportionsas to impart to the rubber base the desired degree of softness, I amenabled to secure a product which, upon vulcanization, will possess thedesired degree of elasticity and have a smooth, velvety finish; and onewhich if placed under con tinuous stretch, will not take a high permanent set. I have found that a composition in which about five parts ofrubber to four parts of the petrolatum or softening agent, are used,give highly satisfactory results and that the proportion of thepetrolatuin may be reduced to fifteen parts of petrolatuin to onehundred parts of rubber without any substantial loss in the quality ofthe product. I contemplate the addition of a substance to qaiicken thecure of the compound, such as anilin oil, and find that the of threeparts of such oil to one hundred of rubber and-eighty parts ofpetrolaturn, give satisfactory results. a

proportions of rubber and the soften agent, or of the for quichening Lhcuring of the compound, may be varied to the desired quality of theprod.-

not; For instance, a compound composed of a smaller proportion ofpetrolatum'and anilin will give a very excellent product which willstand up Well under the ordinary conditions of use in such articles asinner tubes for vehicle tires. e

In the compoundin ofthis rubber compound, .various expedlentshave beenpractised, such as milling the crude rubber and the 'etrolatum in theusual manner, but it has een found that ordinary mixing conditions donot'combine the ingredients in a manner to secure the desired results. Ihave discovered, however, that if after mixing the ingredientsmechanically in any desired manner, the mixture is subjected to theaction of heat of'a temperature above that of the melting point of thesoftening agent, as by subj ecting the. mixture to steam, there' is a.n1ore thorough blending of the rubber and unctuous material to form ahomogeneous mixture and the compound when'vulcanized, will have thedesired char-- acteristics. If thetmlca'nizing medium be mixed with thecompound at the same time as the softening agents, care must be takenthat the temperature to which the batch is subjected, does not reach thevulcanizing degree, but the time or manner of mixing in the vulcanizingmedium, or the load- .ingmaterial, when such.is used, is nonessential tomy invention, and such may be incorporated in the mixture at any timeprior to the vulcanization thereof. I have found the heating of themixture after, or during ;the incorporationtherein of the petrolatum, orother softening agent, to be essential however.

Having ,described my invention, what I claim as new and desire to haveprotected by Letters Patent is:

'1. A methodofmakin rubber compounds consisting in mixing hig gradestifi', anilin I rubber and an unctuous softening agent in suchproportions as to impart to the comtion of heat at a temperature topermit thor- 'ough penetration of the softening agent to produce ahomogeneous material.

2. A method of making rubber compounds, consisting in mechanicallymixing high grade stiff rubber, anilin oil and an unctuous softeningagent in such proportions as to impart to the compound, aftervulcanization, softness, a high degree of elasticity and smoothness .oftexture, and subjecting the mixture to the action of steam at atemperature to ermit thorough penetration of the softening agenttoproduce a homogeneous material.

3. A method of making rubber compounds consisting in mixing- Ceylonrubber, a relatively small amount of anilin oil, and petrolatum in suchproportions as to impart to the compound, after vulcanization, softness,a high degree of elasticity and smoothness of texture and subjecting themixture to the action of heat at a temperature to per-' consisting inmixing'in the presence of open steam Ceylon rubber, a relatively smallamount of anilin oil, and petrolatum in such proportions "as to impartto the compound, after vulcanization, softness, a high degree ofelasticity and smoothness of texture, and

thereafter subjecting the mixture to the,-

action of steam at a'temperature to permit thorough penetration of thepetrolatum to produce a homogeneousmaterial.

Signed at Detroit, county of Wayne and State of Michigan, this 28th dayof February, 1914.

ERWI'N E. A. G. MEYER. Witnesses: 1

J. H. SWIE'I E. LA Bnscmawsmr.

